Under high - boost conditions, the stock actuator's weak spring allows the wastegate to blow open, limiting midrange torque. Bleed orifices (also known as boost foolers) just make it worse. Only Banks solves this problem by replacing the boost actuator. BigHead holds the wastegate closed for quicker boost, then controls the opening to maintain peak boost for superior acceleration and mid - range pulling power. Banks exclusive BigHead wastegate actuator prevents wastegate blow - open by keeping the valve seated at higher pressures, increasing mid - range torque and top - end power.